In recent years an increasing number of systems have been developed in the mm-wave and terahertz frequency ranges. At these high frequencies (e.g., 50-500 GHz), wavelengths can approach sub-millimeter dimensions. With such wavelength scales, the mechanical alignment of waveguide and antenna components becomes increasingly difficult. Antenna characterization techniques, such as those used in extrapolation measurements, near field measurements, and general spatial antenna characterization require the precise positioning of antenna components.
At these frequencies, new techniques must be developed for achieving the same alignment tolerances that have been traditionally straightforward to achieve in the MHz and lower GHz regimes. Although other alignment approaches using laser tracking systems have been previously proposed, a new approach is disclosed herein including a compact optical alignment tool that utilizes polarization-selective optical elements and imaging optics to simultaneously capture and align, in real-time, two digital images of the components that are to be aligned along a common axis to within sub-wavelength precision and accuracy.